Evaluation of Osteomyelitis in Diabetic Foot Patients by MR Imaging

Magnetic resonance imaging (MRI) is the state-of- the-art diagnostic tool for a full evaluation of the foot. MRI allows a fine evaluation of the bone marrow, tendons, muscles, ligaments, capsules and bursae. MRI combines the advantage of visualization of the bony structures, as well as all the soft tissues about the foot and in any plane desirable.MRI, with its high spatial and contrast resolution, is the most helpful in the evaluation of numerous pathologic processes in diabetic foot, especially subtle soft tissue changes, that are not detectable with other imaging methods. MRI is the best imaging modality to detect any soft tissue abnormality. It is used to evaluate the presence or absence of disease, evaluate its extent and identify possible sites for biopsy.Despite high sensitivity, MRI lacks specificity in the diagnosis of osteomyelitis. MRI has a negative predictive value for osteomyelitis close to 100% . Many disorders can produce similar abnormalities in bone marrow signal intensity including: tumors, fractures and surgical alteration.Pedal complications of diabetes have long presented a challenge for the clinician and radiologist predominately related to the difficulty in distinguishing infection from neuroarthropathy. The spectrum of diabetic foot infections is broad, ranging from callous and ulcer formation, to septic arthritis, abscess formation, and osteomyelitis. This article summarizes the MR imaging findings in the diabetic foot and the optimal pulse sequences. Focus is placed on aids in differentiating diabetic infection from other entities and increasing the specificity of diagnosing diabetic foot complications.Key words : (not more than Ten)